JP5153472B2 - Method for manufacturing exothermic sheet, and exothermic sheet - Google Patents

Description

  The present invention relates to a method for manufacturing a heat generating sheet and a heat generating sheet.

  For example, a floor heating apparatus in which a sheet heating element is laid on a joist under a floor of a house or on a concrete area via a heat insulating material and a floor board or the like is laid thereon is widely adopted. In this type of floor heating device, a metal foil is laminated on an insulating sheet such as a plastic sheet, and this metal foil is etched to form a heat generation pattern, or a heat generation pattern groove is formed on the upper surface of a thick insulation sheet. In some cases, a nichrome wire whose outer periphery is insulated is inserted into the groove. In addition to this, there is also a heat generating sheet in which two electrodes are sandwiched between two conductive sheets formed by melting a pallet in which fine powder of carbon is mixed in plastic and forming it into a sheet shape.

As a method for producing the heat generating sheet, for example, a method for producing a stretched film called a tubular method is known. In the tubular method, molten plastic is extruded into a cylindrical shape from an annular nozzle attached to an extrusion molding machine, and at the same time, two electrodes are fed into the cylindrical body while the molded body is in a softened state. It is pressed between two pinch rolls to form a flat plate, and electrode wires are held between both ends. And it heat-cools, producing the heat_generation | fever sheet | seat, forming an electrical joining state between an electrode wire and a molded object.
In addition, as a manufacturing method that solves various problems in this tubular method, the conductive plastic is melted and branched into a plurality of flow paths, and this is flown into a plurality of sheets from a die having a linear slit. While extruding in parallel, arrange two electrode wires near both ends between the two molded sheets facing each other and feed them simultaneously, then press and bond the plurality of molded sheets while holding the electrode wires In addition, a technique for forming a single heat generating sheet is also known (see, for example, Patent Document 1).
JP 2003-17226 A

However, when forming a heat generating sheet by using a metal material having low heat elasticity compared to plastic as an electrode wire and joining two conductive sheets sandwiching the electrode wire by heat fusion, this heat fusion is used. Although the conductive sheet sometimes expands and shrinks with cooling, the expansion and contraction of the electrode wire does not follow this contraction, so that the conductive sheet is wavy and becomes a comb-like state. there were. In particular, when a heat generating sheet is used as a building material, a long heat generating sheet of about 2 meters is formed, so that a large expansion and contraction of 20 mm occurs even if the expansion and contraction amount at the time of heat fusion is about 1%, and the waviness due to this is extremely high. It will be remarkable.
In addition, when a heat generating sheet is used in the floor heating device, there is a problem that the heat generating sheet in which undulation has occurred causes the floor to rise.
This invention is made | formed in view of the situation mentioned above, The objective is to provide the manufacturing method of the heat generating sheet which can shape | mold the heat generating sheet excellent in flatness favorably, and a heat generating sheet.

  In order to achieve the above object, the present invention is a method for manufacturing a heat generating sheet in which an electrode wire is disposed between two conductive sheets along an edge portion of these conductive sheets. Between the conductive sheets, a resin material is arranged in a portion excluding the electrode wire arrangement planned portion where the electrode wires are arranged, and these are formed into an integral sheet by thermocompression bonding, and then the electrode wire arrangement The electrode wire is disposed in the planned portion, and the edge portion of the conductive sheet is heat-pressed.

  Moreover, the present invention is characterized in that, in the method for manufacturing a heat generating sheet according to the present invention, the resin material has an insulating property and melts due to abnormal heat generated in the conductive sheet.

  Moreover, the present invention is characterized in that, in the above-described method for manufacturing a heat generating sheet according to the present invention, the resin material is formed to a thickness comparable to the electrode wire.

  In order to achieve the above object, the present invention arranges a thermocompression-preventing material along the edge of these conductive sheets between the two conductive sheets, and heats these conductive sheets. It is characterized by being formed into an integral sheet by crimping, removing the thermo-compression-preventing material from the edge, placing an electrode wire on the removed part, and thermo-compressing the edge.

  Further, the present invention provides the method for producing a heat generating sheet according to the present invention described above, wherein the electrode wire is a plurality of the electrode wires that are sunk into the conductive sheet in contact with the conductive sheet as the pressure is applied. The protrusion is formed.

  In order to achieve the above object, the present invention arranges a resin material between the two conductive sheets except for the electrode wire arrangement planned portion where the electrode wire is arranged, and thermocompression-bonds them. The heat generating sheet is formed by forming the electrode wire on the electrode wire arrangement planned portion and then thermocompression bonding the edge portion of the conductive sheet.

  According to the present invention, between the two conductive sheets, the resin material is arranged in a portion excluding the electrode wire arrangement scheduled portion where the electrode wire is arranged, and these are formed by heating and press-bonding to form an integral sheet. After that, since the electrode wires are arranged in the electrode wire arrangement planned portion and the edge portion of the conductive sheet is heat-pressed, the heat generating sheet excellent in flatness can be manufactured without generating undulation.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the drawings shown below, in order to facilitate understanding of the invention, the thicknesses of the electrode wires 7 and 9 are exaggerated from the actual ones.
[First Embodiment]
FIG. 1 is a perspective view of a heat generating sheet 1 according to the present embodiment, and FIG. 2 is a cross-sectional view of the heat generating sheet 1.
The heat generating sheet 1 includes two conductive sheets 3 and 5 which are overlapped and bonded to each other, two electrode wires 7 and 9 sandwiched between the conductive sheets 3 and 5, and these electrodes It is formed with an insulating resin material 11 disposed between the wires 7 and 9, and is suitable for use as a planar heating element used for floor heating or the like (more specifically, for building materials. (Suitable dimensions).
The conductive sheets 3 and 5 are prepared by uniformly mixing pellets produced by attaching about 15 to 30% of fine conductive carbon, for example, furnace black to a thermoplastic, in a mixer, and then using a forming machine. A long rectangular sheet is used.

For the electrode wires 7 and 9, a slightly flat braided wire or a flat metal foil that is braided using a number of thin copper wires is used.
These electrode wires 7 and 9 are disposed along the left and right edge portions 13A and 13B along the longitudinal direction of the conductive sheets 3 and 5, and electrical wiring connectors are connected to the respective front end portions 7A and 9A. Then, the electrode lines 7 and 9 are energized with different polarities. When electric power is supplied to the electrode wires 7 and 9, a current flows between the electrode wires 7 and 9 through the conductive sheets 3 and 5, and the conductive sheets 3 and 5 generate heat along with the current. Acts as a heating element.

The insulating resin material 11 is formed by forming an insulating resin into a plate shape that extends together with the conductive sheets 3 and 5. The insulating resin material 11 is formed to have a thickness similar to that of the electrode wires 7 and 9, and electrode lines having a width XA are planned to be arranged on the left and right edges 13 A and 13 B of the conductive sheets 3 and 5, respectively. The width 15 is such that the portion 15 can be provided.
For this insulating resin material 11, for example, paraffin or polyethylene (PE) is used, and an overcurrent flows through the electrode wires 7, 9. For example, when it reaches 100 ° C. to 200 ° C., it melts and wraps around the electrode wires 7 and 9. Thereby, since the electrode wires 7 and 9 are covered with the insulating resin material 11, the flow of current between the electrode wires 7 and 9 is stopped, and heat generation is quickly suppressed.

A method for manufacturing such a heat generating sheet 1 will be described with reference to conceptual diagrams shown in FIGS. 3 and 4. In these drawings, the thicknesses of the electrode wires 7, 9 and the like are shown larger than the actual thickness in order to easily grasp the configuration between the conductive sheets 3, 5.
Between the two conductive sheets 3 and 5 formed by the forming machine, as shown in FIG. 3, plate-like insulating resin material 11 extending together with these conductive sheets 3 and 5 is provided with electrodes on the left and right sides thereof. The line arrangement | positioning plan part 15 is provided, it pinches | interposes, and hot air is applied to these, and it presses between between press roller 20A, 20B, heating. Thereby, the conductive sheets 3 and 5 are fused and joined to the insulating resin material 11. At this time, in the electrode line arrangement scheduled portion 15, the insulating resin material 11 has a gap between the conductive sheets 3 and 5, and thus passes through the pressing rollers 20 </ b> A and 20 </ b> B without being joined.

  In the step of heat-sealing the conductive sheets 3 and 5 to the insulating resin material 11, the conductive sheets 3 and 5 are stretched by heating and pressurization at the time of heat-sealing, and shrinkage is generated with cooling. . At this time, electrode wires 7 and 9 having extremely different thermoplasticity are not disposed between the conductive sheets 3 and 5, and the resin insulation that can follow the expansion and contraction of the conductive sheets 3 and 5 due to heat. Since the conductive resin material 11 is disposed, when the conductive sheets 3 and 5 are shrunk by cooling, the wavy deformation along the longitudinal direction does not occur.

Next, as shown in FIG. 4, the electrode wires 7 and 9 are respectively arranged on the left and right electrode line arrangement scheduled portions 15 of the insulating resin material 11, and then the left and right edge portions 13 </ b> A of the conductive sheets 3 and 5. , 13B are pressed by the pressing rollers 22A, 22B, 24A, 24B while applying hot air, so that the edges 13A, 13B of the conductive sheets 3, 5 are joined to the electrode wires 7, 9.
In the thermal fusion process of the edge portions 13A and 13B, the edge portions 13A and 13B of the conductive sheets 3 and 5 are heated for thermal fusion and are pressed by the pressure rollers 22A, 22B, 24A and 24B. Some elongation occurs. However, since most of the conductive sheets 3 and 5 excluding the electrode wire arrangement planned portion 15 have already been heat-sealed, since the elongation of the edge portions 13A and 13B due to heating in this step is suppressed, the wavy shape No deformation occurs.

  In addition, as described above, since the thickness of the insulating resin material 11 is approximately the same as the thickness of the electrode wires 7 and 9, when the thickness of the insulating resin material 11 is thinner than the electrode wires 7 and 9, Alternatively, when the edges 13A and 13B of the conductive sheets 3 and 5 are heat-sealed as compared with the case where the insulating resin material 11 is not provided, undulations due to the electrode wires 7 and 9 are formed on the surfaces of the conductive sheets 3 and 5. The exothermic sheet 1 having no flatness and excellent flatness is obtained.

Here, in the step of heat-sealing the conductive sheets 3 and 5 to the insulating resin material 11 and the step of heat-sealing the edges 13A and 13B of the conductive sheets 3 and 5, respectively, the insulating resin material Since heat is applied to the insulating resin material 11, the insulating resin material 11 is somewhat melted, which may affect the electrode wires 7 and 9 disposed on the left and right sides of the insulating resin material 11.
Therefore, as shown in FIG. 2, the electrode line arrangement scheduled portion 15 is provided with a gap 30 having a predetermined width Y between the insulating resin material 11 and the electrode wires 7 and 9. The insulating resin material 11 is configured not to affect the electrode wires 7 and 9 even if 11 is somewhat melted in the heat sealing process.

As described above, in the present embodiment, when the heat generating sheet 1 is manufactured, a portion excluding the electrode line arrangement scheduled portion 15 where the electrode lines 7 and 9 are arranged between the two conductive sheets 3 and 5. In the state where the insulating resin material 11 is disposed on the substrate, these are heat-pressed to form an integral sheet, and thereafter, the electrode wires 7 and 9 are disposed on the electrode wire placement planned portion 15, and the electrode wire placement planned portion 15 is formed. The heat generating sheet 1 was formed by thermocompression bonding.
According to this, when the conductive sheets 3 and 5 are heat-sealed, the electrode wires 7 and 9 having extremely different thermoplasticity are not disposed between the conductive sheets 3 and 5, Since the insulating resin material 11 made of resin capable of following the expansion and contraction due to heat of the conductive sheets 3 and 5 is disposed, when the conductive sheets 3 and 5 contract by cooling, the wavy deformation along the longitudinal direction Will not occur.
In addition, since most of the electrodes excluding the electrode wire arrangement planned portion 15 are already heat-sealed, the electrode wires 7 and 9 are arranged on the electrode wire arrangement planned portion 15 and the edges 13A and 13B are heat-sealed. Since the elongation at the time of thermocompression bonding of the edge portions 13A and 13B is suppressed, the wavy deformation due to the shrinkage at the time of cooling does not occur, and the heat generating sheet 1 having excellent flatness can be obtained.

  In the present embodiment, the insulating resin material 11 has an insulating property and melts due to abnormal heat generated in the conductive sheets 3 and 5, so that the electrode wires 7 and 9 are wrapped by this melting. Thus, the electrode wires 7 and 9 are insulated from the conductive sheets 3 and 5. As a result, when abnormal heat generation occurs in the conductive sheets 3 and 5, the current flow from the electrode wires 7 and 9 to the conductive sheets 3 and 5 is stopped, so that the heat generation can be quickly suppressed. Therefore, the heat generating sheet 1 excellent in safety can be obtained.

  Moreover, in this embodiment, since the insulating resin material 11 is formed in the same thickness as the electrode wires 7 and 9, when the thickness of the insulating resin material 11 is thinner than the electrode wires 7 and 9, etc. In comparison, when the edges 13A and 13B of the conductive sheets 3 and 5 are heat-sealed, the surface of the conductive sheets 3 and 5 does not undulate due to the electrode wires 7 and 9, and the heat generation is excellent in flatness. Sheet 1 is obtained.

  By using the heat generating sheet 1 having excellent flatness as described above in, for example, a floor heating device, a floor heating device free from a floor lift can be obtained. Moreover, since the heat generating sheet 1 can be brought into contact with the heat storage material included in the floor heating device without any gap, an efficient floor heating device can be realized.

[Second Embodiment]
In the above-described first embodiment, the insulating resin material 11 is disposed between the two conductive sheets 3 and 5, and these are heat-sealed in a state where a gap is generated in the electrode wire placement planned portion 15. Thus, the two conductive sheets 3 and 5 are joined together leaving the electrode line arrangement scheduled portion 15.
On the other hand, in the present embodiment, when the two conductive sheets 3 and 5 are bonded by thermal fusion, the thermocompression-preventing material 40 is arranged in advance in the electrode wire arrangement scheduled portion 15, The two conductive sheets 3 and 5 are joined together leaving the electrode line arrangement scheduled portion 15.

More specifically, as shown in FIG. 5, between the two conductive sheets 3, 5 formed by the forming machine, the thermocompression-preventing material 40 is provided and sandwiched along the electrode wire arrangement scheduled portion 15, The hot air is applied to these and heated while being pressed between the pressing rollers 20A and 20B. Thereby, the electroconductive sheets 3 and 5 are joined except the electrode wire arrangement | positioning scheduled part 15. As shown in FIG.
By this joining, the conductive sheets 3 and 5 are stretched and contracted with cooling, but the electrode wires 7 and 9 having extremely different thermoplasticity are disposed between the conductive sheets 3 and 5. Therefore, no wavy deformation occurs.
In addition, since the electrode line arrangement | positioning plan part 15 of this embodiment does not need to provide the clearance gap 30 of the predetermined width Y in the electrode lines 7 and 9, if it has the width | variety Xb of the extent which the electrode lines 7 and 9 can be accommodated. good.

Next, as shown in FIG. 6, after removing the thermocompression-preventing material 40 from the electrode wire placement planned portion 15, the electrode wires 7 and 9 are placed on the electrode wire placement planned portion 15, respectively. Thereafter, the left and right edges 13A and 13B of the conductive sheets 3 and 5 are pressed by the pressing rollers 22A, 22B, 24A and 24B while applying hot air to the edges, respectively, so that the edges 13A and 13A of the conductive sheets 3 and 5 are pressed. 13B is heat-sealed and sealed.
In the thermal fusion process of the edge portions 13A and 13B, most of the edge portion excluding the electrode wire arrangement scheduled portion 15 has already been thermally fused, so that the elongation of the edge portions 13A and 13B due to heating in this step can be suppressed. Therefore, no wavy deformation occurs due to shrinkage during cooling.

FIG. 7 is a diagram schematically showing a cross section of the heat generating sheet 100 of the present embodiment.
In the heat generating sheet 100, nothing is disposed between the two conductive sheets 3, 5 other than the electrode wires 7, 9. Therefore, depending on the thickness of these electrode lines 7, 9, the heat generating sheet 100 Some relief occurs on the surface.
Therefore, in the present embodiment, in order to prevent the occurrence of undulations due to the electrode wires 7 and 9, a configuration in which a large number of mountain-shaped protrusions 44 are provided on the contact surface 42 that contacts the conductive sheet 5 of the electrode wires 7 and 9 is provided. Yes.
With this configuration, when the edges 13A and 13B of the conductive sheets 3 and 5 are heat-pressed and heat-sealed, the electrode wires 7 and 9 sink into the conductive sheet 5 by pressurization, so that the electrode wires 7 , 9 can suppress the occurrence of undulations.

As described above, according to the present embodiment, the thermocompression-preventing material 40 is disposed between the two conductive sheets 3 and 5 along the edges 13A and 13B of the conductive sheets 3 and 5, The conductive sheets 3 and 5 are heat-pressed to form an integral sheet, the heat-pressure-bonding prevention material 40 is removed from the edge portions 13A and 13B, and the electrode wires 7 and 9 are disposed on the removed portions. The heat generating sheet 100 was manufactured by thermocompression bonding the parts 13A and 13B.
According to this, when the conductive sheets 3 and 5 are heat-sealed, the electrode wires 7 and 9 having extremely different thermoplasticity are not disposed between the conductive sheets 3 and 5. When the conductive sheets 3 and 5 are shrunk by cooling, the wavy deformation along the longitudinal direction does not occur.
In addition, since most of the electrodes excluding the electrode wire arrangement planned portion 15 are already heat-sealed, the electrode wires 7 and 9 are arranged on the electrode wire arrangement planned portion 15 and the edges 13A and 13B are heat-sealed. Since the elongation at the time of thermocompression bonding of the edge portions 13A and 13B is suppressed, a wavy deformation due to shrinkage at the time of cooling does not occur, and the heat generating sheet 100 having excellent flatness can be obtained.

  Furthermore, according to the present embodiment, a large number of mountain-shaped protrusions 44 are provided on the contact surface 42 of the electrode wires 7 and 9 that contact the conductive sheet 5, and the edges 13A and 13B of the conductive sheets 3 and 5 are heated. Since the electrode wires 7 and 9 are submerged into the conductive sheet 5 by pressurization when being pressed and heat-sealed, the generation of undulation due to the electrode wires 7 and 9 is suppressed, and the heat generating sheet 100 with higher flatness is provided. Is obtained.

[Third Embodiment]
In the first and second embodiments described above, the two conductive sheets 3 and 5 are heat-sealed, leaving the electrode line arrangement scheduled portion 15, and then the electrode lines 7, 9 was arranged, and the electrode wire arrangement scheduled portion 15 was heat-sealed to form the heat generating sheets 1 and 100.
On the other hand, in the heat generating sheet 200 of the present embodiment, the electrode wires 7, 9 are not heat-sealed after the electrode wires 7, 9 are arranged in the electrode wire arrangement scheduled portion 15, as shown in FIG. A conductive adhesive 35 is applied between the electrode wires 7 and 9 arranged in the electrode line arrangement scheduled portion 15 having a width XC corresponding to a width of 9 and the conductive sheets 3 and 5, and the pressing rollers 22A, 22B, The conductive sheets 3 and 5 are joined to the electrode wires 7 and 9 by being pressed by 24A and 24B.
Thereby, since it is not necessary to join the edge parts 13A and 13B of the conductive sheets 3 and 5 by thermal fusion, it is possible to arrange the electrode wires 7 and 9 so as to be aligned with the end parts of the edge parts 13A and 13B. In addition, since the heat sealing step for joining the edges 13A and 13B of the conductive sheets 3 and 5 is unnecessary, the above-described wavy deformation does not occur, and heat generation with excellent flatness is achieved. A sheet 200 is obtained.
In addition, in this embodiment, it is not restricted to the structure which fixes the electrode wires 7 and 9 to the electroconductive sheets 3 and 5 using the electroconductive adhesive 35, The surface of the electrode wires 7 and 9 which contact | connect the electroconductive sheets 3 and 5 It is good also as a structure which provides the processus | protrusion with which the many front-end | tips pierced in the electroconductive sheets 3 and 5 were pointed, and fixed the electrode wires 7 and 9 to the electroconductive sheets 3 and 5 with these processus | protrusions.

  Note that each of the above-described embodiments is merely an aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention.

It is a perspective view showing the composition of the exothermic sheet concerning a 1st embodiment of the present invention. It is sectional drawing of the same heat generating sheet. It is a figure showing a manufacturing method of the exothermic sheet. It is a figure showing a manufacturing method of the exothermic sheet. It is a figure which shows the manufacturing method of the heat generating sheet which concerns on 2nd Embodiment. It is a figure showing a manufacturing method of the exothermic sheet. It is sectional drawing of the same heat generating sheet. It is sectional drawing of the heat generating sheet which concerns on 3rd Embodiment.

Explanation of symbols

1,100,200 Heat generation sheet 3,5 Conductive sheet 7,9 Electrode wire 11 Insulating resin material 13A, 13B Edge 15 Electrode line arrangement planned portion 35 Conductive adhesive 40 Heat pressure bonding prevention material 42 Contact surface 44 Projection

Claims (6)

A method for producing a heat generating sheet in which electrode wires are arranged along the edges of these conductive sheets between two conductive sheets,
Between the two conductive sheets, a resin material is arranged in a portion excluding the electrode wire arrangement planned portion where the electrode wires are arranged, and these are thermocompression bonded to form an integral sheet, A method for producing a heat generating sheet, wherein the electrode wire is arranged in an electrode wire arrangement scheduled portion, and an edge portion of the conductive sheet is thermocompression bonded.   The method for producing a heat generating sheet according to claim 1, wherein the resin material has an insulating property and melts due to abnormal heat generated in the conductive sheet.   The method for manufacturing a heat generating sheet according to claim 1, wherein the resin material is formed to have a thickness comparable to that of the electrode wire.   Between the two conductive sheets, a thermocompression-preventing material is disposed along the edges of these conductive sheets, and these conductive sheets are thermocompression-bonded to form an integral sheet. The method for producing a heat generating sheet is characterized in that the thermocompression-preventing material is removed from a portion, an electrode wire is disposed on the removed portion, and the edge portion is thermocompression bonded.   The said electrode wire is formed in the surface which contact | connects the said electroconductive sheet with the some protrusion which sinks the said electrode wire in the said electroconductive sheet with pressurization. Manufacturing method of heat generating sheet.   Between the two conductive sheets, a resin material is arranged in a portion excluding the electrode wire arrangement planned portion where the electrode wire is arranged, and these are heated and pressed to form an integral sheet, and then the electrode wire A heat generating sheet, wherein the electrode wire is disposed in a portion to be disposed, and an edge portion of the conductive sheet is formed by thermocompression bonding.

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